JP2011213849A - Polyamideimide resin material, polyamideimide solution, and polyamideimide thin film - Google Patents

Abstract

An object of the present invention is to provide a polyamideimide resin having a high transparency with a light transmittance of 80% or more at a measurement wavelength of 400 nm.
A polyamideimide resin synthesized from a diamine anhydride (for example, anhydrous cyclohexanetricarboxylic acid chloride) and a diamine is provided. For example, the polyamideimide resin exhibits a solubility of 20% by weight or more in an organic solvent, and the organic solvent is one kind selected from N-methylpyrrolidone, γ-butyrolactone and cyclopentanone or a mixed solution thereof. It is characterized by being.
[Selection figure] None

Description

  The present invention relates to a polyamideimide resin material, a polyamideimide solution, and a polyamideimide thin film.

  The use of low power consumption products and clean energy has been demanded due to the effects of global warming, etc., and there has been a demand for high quality display devices such as flat-screen TVs, solar cells and solar water heaters with low power consumption. Yes. The demand for protective films for these display devices, transparent resins and transparent sheets used as coating agents for solar battery panels and solar water heaters, etc. has increased, and sufficient mechanical strength and heat resistance have been required. Yes.

  In order to satisfy these requirements, for example, there is a transparent polyimide resin as shown in Patent Document 1, and by forming a thin film by applying a transparent polyamic acid solution or the like, the necessary mechanical strength is ensured while ensuring transparency. It is possible to ensure heat resistance and chemical resistance.

  However, the raw materials were special and expensive. Further, the polyamic acid solution requires high-temperature treatment for a long time before imidization after coating, and has been a major obstacle for general use.

  On the other hand, the conventional polyamideimide resin is obtained by the reaction of trimellitic anhydride and aromatic diamine, and has excellent thermal stability and toughness unmatched by other engineering plastics. In addition, it has excellent heat resistance (for example, continuous use temperature of 260 ° C.), mechanical strength, and excellent slidability at high temperatures. Furthermore, some polyamideimide resins may be soluble in N-methylpyrrolidone after completion of imidization.

JP-A-9-95533

However, for example, “SOXR”, which is an organic solvent-soluble polyamideimide provided by the applicant, is not sufficiently transparent in the visible light region and has a yellowish color. Furthermore, it was soluble only in the organic catalyst NMP (N-methylpyrrolidone), and its use was limited.
For this reason, realization of the polyamide-imide resin which ensured transparency was awaited.

  This invention is made | formed in view of said subject, Comprising: It aims at providing the heat resistant transparent polyamide-imide resin material which realized transparency, a polyamide-imide solution, a polyamide-imide thin film, etc.

As a means for solving the above-described problem, an embodiment of the present invention according to the present invention has the following configuration.
That is, a polyamide-imide resin material synthesized from tricarboxylic anhydride chloride and diamine is used. For example, the anhydrous tricarboxylic acid chloride is anhydrous cyclohexane tricarboxylic acid chloride.

For example, it is set as the polyamide imide resin material which shows the solubility of 20 weight% or more with respect to an organic solvent.
Further, for example, the organic solvent is one selected from N-methylpyrrolidone, γ-butyrolactone and cyclopentanone or a mixed solution thereof.

Alternatively, a polyamide-imide resin film characterized by using any of the polyamide-imide resin materials described above.
For example, the polyamideimide resin film is characterized in that the light transmittance at a measurement wavelength of 400 nm is 80% or more.

  ADVANTAGE OF THE INVENTION According to this invention, transparency can be implement | achieved and the polyamide-imide resin material, the polyamide-imide solution, and the polyamide-imide thin film which have heat resistance can be provided.

  Hereinafter, an embodiment of an invention according to the present invention will be described in detail. In this embodiment, a transparent polyamide-imide resin material, a polyamide-imide thin film, and a polyamide-imide solution excellent in heat resistance and mechanical strength that can be realized by a relatively inexpensive material will be described.

  In this embodiment, a polyamideimide resin is synthesized from tricarboxylic anhydride chloride and diamine. As the anhydrous tricarboxylic acid chloride, it is more preferable to use anhydrous cyclohexane tricarboxylic acid chloride. For example, the polyamide-imide resin material has a solubility of 20% by weight or more with respect to the organic solvent shown below.

As the organic solvent, for example, one kind selected from N-methylpyrrolidone, γ-butyrolactone and cyclopentanone or a mixed solution thereof can be used.
As the diamine synthesized with tricarboxylic anhydride chloride, it is desirable to use 4,4-oxydianiline (hereinafter referred to as “4,4-ODA”) represented by Structural Formula 1. However, as a diamine compound, it is not limited to 4, 4-ODA, For example, the following diamine compounds can also be used.

(1) PPD: p-phenylenediamine (2) MPD: m-phenylenediamine (3) 3,4-ODA: 3,4′-oxydianiline (4) ASD: 4,4′-thiodianiline (5) HFBAPP : 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane (6) BAPS: bis [4- (4-aminophenoxy) phenyl] sulfone (7) O-TB: O-tolidine
(8) m-TB: m-tolidine (9) TFMB: 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl (10) MDA: 4,4′-methylenedianiline (11) DABP: 4,4'-diaminobenzophenone

First, a process for producing a polyamide-imide powder that will be a polyamide-imide resin material according to an embodiment of the present invention will be described.
(1) Preparation of uniform solution

  27.63 g (0.138 mol) of 4,4-oxydianiline (hereinafter referred to as “4,4-ODA”) represented by Structural Formula 1 was placed in a glass container equipped with a stirrer, a thermometer, and a nitrogen gas introduction tube. First, 300 g of dimethylacetamide (hereinafter referred to as “DMAc”) and 13.96 g (0.138 mol) of triethylamine are added, and the mixture is stirred for a certain time to form a uniform solution.

Structural formula 1 (4,4-ODA)

(2) Preparation of polyamide solution Anhydrous cyclohexanetricarboxylic acid chloride represented by Structural Formula 2 (hereinafter referred to as “CHTAC”) 30 so as not to exceed 40 ° C. while the ice-cooled homogeneous solution was prepared as described above. Slowly add 0.000 g (0.138 mol).
After completion of the addition, the ice cooling is stopped and the reaction is allowed to proceed at room temperature for 2 hours. Then, 0.21 g (0.002 mol) of aniline is added, and the mixture is further stirred for 30 minutes to prepare a polyamide solution having a viscosity of 19 ps.

Structural formula 2 (CHTAC)

(3) Imidization of polyamide solution To the polyamide solution thus prepared, 26 mL of acetic anhydride and 12 mL of pyridine were added and stirred at 55 ° C. for 2 hours to perform imidization.
(4) Preparation of polyamideimide powder The obtained reaction solution was added to a water / methanol mixed solution, and the obtained powder was washed with water and dried to obtain a polyamideimide powder.

Structural formula 3 (: this embodiment)

The results of physical property evaluation of the polyamideimide powder, which is the polyamideimide resin material of the present embodiment prepared as described above, are shown below.
(1) Molecular weight measurement To 3 mg of the obtained polyamideimide powder, DMF added with 3 mL of LiBr was added and dissolved, followed by filtration with 0.45 μm hydrophilic PTFE membrane filter cartridge (Millex-LH, manufactured by Millipore Japan). The ones were measured for molecular weight using gel permeation chromatography.

Measurement conditions Column: TSKgel Super AWM-H 6.0 mm (ID) × 150 mm (L) (Tosoh)
Mobile phase: DFM 10 mM LiBr added Flow rate: 0.6 mL / min.
Detector: RI-101 differential refractometer (manufactured by Showa Denko)
Injection volume: 20 μL
Molecular weight calibration: monodisperse polystyrene
The measurement results are as shown in Table 1.

(2) Measurement of solubility The polyamideimide powder of this embodiment is added to the organic solvent so as to be 20 w%, and the solubility is confirmed. The confirmation method was determined to be soluble by visually confirming that the prepared solution was allowed to stand at room temperature for 15 days and then had no insoluble matter and had fluidity.
The solubility measurement results are shown in Table 2. As a comparison, the solubility of organic solvent-soluble polyamideimide (SOXR manufactured by Nippon Kogyo Paper Industries Co., Ltd.) having a general structure on the market is described.

  Conventional general organic solvent-soluble polyamideimide (SOXR) is soluble only in NMP. NMP is easy to absorb moisture and has a high boiling point. If the moisture is absorbed, the surface of the solution becomes cloudy and then loses fluidity. For example, when coating by screen printing, it is known that the solution (ink) loses fluidity on the plate and becomes unprintable.

For this reason, when using ink using NMP, there are many problems such as requiring a high-temperature drying furnace under strict humidity control (humidity of 40% or less).
However, the polyamide-imide resin material of the present embodiment is soluble in organic solvents such as γ-butyrolactone (GBL) and cyclopentanone (CPN) in addition to NMP which causes these problems. Since these organic solvents can be used, it has been found that a polyamide-imide film can be easily formed by coating and drying without controlling humidity.

(3) Measurement of light transmittance and production of film for measurement A solution in which 28.6 w% of the powder of this embodiment was dissolved in γ-butyrolactone was produced. Using a blade coater, this solution is coated on a glass whose surface has been exfoliated. After drying this at 120 ° C. for about 15 minutes, the coating film was peeled off from the glass, and this was dried at 250 ° C. for 40 minutes to produce a measurement film having a thickness of 25 μm.

-Measurement result The light transmittance of 200-2500 nm was measured for the film for measurement produced as mentioned above using the U-4100 type spectrophotometer by Hitachi High-Tech. As a comparative control, SOXR manufactured by Nippon Kogyo Paper Industry Co., Ltd. and Kapton manufactured by Toray DuPont, which is a typical polyimide film were used. Table 3 shows the measurement results in the range of 200 to 2500 nm, and Table 4 shows the measurement results in the range of 200 to 700 nm.

Table 3 200-2500nm light transmittance

Table 4 200-2500 nm light transmittance

Conventional Kapton and SOXR have absorption in the visible light region (380 to 750 nm), and the appearance is also yellow to dark brown. For this reason, in spite of having high heat resistance, examination to optical related fields such as solar cells, optical waveguides, and lenses that require glass replacement has not progressed.
However, in the present embodiment (development product 1), the transmittance is 85% or more in the visible light region, and colorless and transparent is realized, so that it can be used in these fields.

(3) Measurement of other physical properties / Measurement of tensile strength, elastic modulus and elongation A film having a thickness of 25 μm was prepared and measured in the same procedure as the above-described optical property measurement film. The apparatus used was STROGRAP E-L (manufactured by Toyo Seiki Seisakusho).
Measurement conditions Sample size: 10mm x 130mm
Tensile speed: 100 mm / mim

-Measurement of glass transition temperature and coefficient of thermal expansion A film having a thickness of 25 µm was prepared and measured in the same procedure as the film for measuring optical properties.
The apparatus used was Thermo Plus TMA8310 (manufactured by Rigaku).
Measurement conditions Sample size: 5mm x 15mm
Measurement method: TMA method Measurement range: Room temperature to 300 ° C
Temperature increase rate: 10 ° C / min

-Measurement of refractive index A 25 μm-thick film was prepared and measured in the same procedure as the optical property measurement film.
The apparatus used was an Abbe refractometer (manufactured by Atago Co., Ltd.).
Measurement conditions Test wavelength: D line (589 nm)
Intermediate solution: Methylene iodide Test temperature: 23 ° C

Measurement of dielectric constant A film having a thickness of 25 μm was prepared and measured in the same procedure as the film for measuring optical properties.
The apparatus used was a network analyzer (manufactured by Agilent Technologies).
Measurement conditions Sample size: 3mm x 15mm
Test method: Cavity resonator perturbation method Test frequency: 1 GHz

ポリアミドイミド樹脂が本来持つ高いガラス転移温度を有する。 -Measurement results Table 5 shows the above measurement results.

It has a high glass transition temperature inherent to the polyamide-imide resin.

(4) Comparative Example Using Other Raw Materials Synthesis and Evaluation of Polyamideimide / Comparative Example 1
Synthesis of Comparative Example 29.06 g (0.138 mol) of trimellitic anhydride chloride (Structural Formula 4) (hereinafter referred to as “TAC”) was used in place of 30 g (0.138 mol) of CHTAC of the present embodiment. Except for the above, the synthesis was performed under the same conditions as in the present embodiment (the comparative example has the same structure as “SOXR” manufactured by Nippon Kogyo Co., Ltd.).
Polyamideimide was synthesized using trimellitic anhydride chloride (Structural Formula 4) which is an aromatic tricarboxylic acid derivative instead of CHTAC, and its solubility and light transmittance were measured.

Structural formula 4 TAC

Comparative example 2
Instead of 30 g (0.138 mol) of CHTAC in this embodiment, TAC 29.06 g (0.138 mol) was replaced with 2,2-bis (trifluoromethyl-4,5-diaminobiphenyl (structure) instead of 4,4-ODA. Formula 5) (hereinafter referred to as “TFMB”) Synthesized under the same conditions as in this embodiment, except that 44.19 g (0.138 mol) was used.

Structural formula 5 TFMB

Comparative example 3
Instead of 30 g (0.138 mol) of CHTAC in this embodiment, TAC 29.06 g (0.138 mol) was replaced with 4,4-diaminodicyclohexylmethane (Structural Formula 6) (hereinafter referred to as “DCHM”) instead of 4,4-ODA. The synthesis was attempted under the same conditions as in this embodiment except that 29.02 g (0.138 mol) was used. However, the reaction solution lost its fluidity during stirring and the stirring was difficult. Thus, the aimed polyamideimide could not be obtained.

Structural Formula 6 DCHM

-Measurement of solubility and light transmittance of comparative example The solubility in organic solvents of Comparative Examples 1 to 3 and the light transmittance at 400 nm were measured.
The measurement method was the same as that in this embodiment. However, when the sample film for light transmittance measurement was prepared, a material insoluble in γ-butyrolactone was dissolved in NMP to form an ink, and a film was obtained by the same method and conditions.

-Measurement results Table 6 shows the measurement results.

Only the product of this embodiment has achieved high light transmittance (colorless) and solubility at 400 nm.
From this, it has also been found that in order to achieve both high light transmittance (colorless) and solubility, it is not possible to use TAC as a tricarboxylic acid derivative, but only when CHTAC is used.

Claims (7)

A polyamide-imide resin material synthesized from tricarboxylic anhydride chloride and diamine. 2. The polyamide-imide resin material according to claim 1, wherein the tricarboxylic anhydride chloride is anhydrous cyclohexane tricarboxylic chloride. The polyamide-imide resin material according to claim 1, wherein the polyamide-imide resin material has a solubility of 20% by weight or more with respect to an organic solvent. 4. The polyamide-imide resin material according to claim 3, wherein the organic solvent is one selected from N-methylpyrrolidone, γ-butyrolactone and cyclopentanone or a mixed solution thereof. A polyamideimide solution in which the polyamideimide resin material according to any one of claims 1 to 4 is dissolved in the organic solvent. A polyamideimide resin film using the polyamideimide resin material or solution according to any one of claims 1 to 5. 7. The polyamideimide resin film according to claim 6, wherein the light transmittance at a measurement wavelength of 400 nm is 80% or more.